✍ Scribed by L. Cassidei; O. Sciacovelli
No coin nor oath required. For personal study only.
An analysis of the 'H and 19F NMR spectra of 2-fluoronaphthalene was performed. 'H-19F inter-ring coupling constants were found to be positive over an even number of intervening bonds between the coupled nuclei and negative over an odd number. Such a sign alternation was based on a positive value for the hypefine interaction constant of the fragment C-F. Theoretical computation based on the finite perturbation theory (FPT) in the MO INDO approximation gives 'H-"F inter-ring coupling constant values which are in satisfactory agreement with the experimental ones. 'H-'H coupling constants follow the expected trend.
📜 SIMILAR VOLUMES
In the course of our studies on the synthesis of anthracyclines [I-41 based on the Diels-Alder additions of exocyclic s-cis-butadiene moieties grafted onto 7-oxabicyclo[2.2. Ilheptane derivatives 1, we observed 'H-NMR spectra of the corresponding adducts 2 with measurable homoallylic 'J(H,H) couplin
## Abstract The signs of all ^13^C^19^F and ^1^H–^19^F coupling constants in fluorobenzene, some substituted derivatives, and in 2‐fluoropyridine have been related using single‐frequency ^13^C{^1^H} double resonance techniques. All ^13^C^19^F couplings in these compounds are shown to be positive